The Incidence of Common Complications, Including Ectropion and Entropion, in Transconjunctival and Subciliary Approaches for Treatment of ZMC Fractures

Statement of the Problem: Treating zygomaticomaxillary complex fractures (ZMC Fx) can result in postoperative complications that should be minimized by choosing the best surgical approach. Purpose: This study compared incidence rates of some common postoperative complications with emphasis on ectropion (an outward curling of the lower eyelid) and entropion (an inward curling of the lower eyelid) occurring with transconjunctival or subciliary approaches for the treatment of ZMC fractures. Materials and Method: This prospective study enrolled 80 patients with ZMC Fx who had been surgically treated. Patients were visited within one month and five months postoperatively by the same surgeon. An information checklist was completed for each patient for clinical assessment of postoperative complications. Results: There was no significant difference between the two groups in the type of trauma (simple or comminuted) (p= 0.1) or the frequency of ectropion and entropion one month and five months postoperatively (p> 0.05). The same results were observed for history of massage under the eye or around the field of surgery (p= 0.151), scleral show (p= 0.414), history of post-surgical epiphora (overflow of tears and accumulation of tear) (p= 0.059), duration of the use of suspension/frost sutures (used to prevent eyelid distortion secondary to wound injury applied at the skin inferior to the incision to help elevate the lid) (p= 0.057), and the use of porex (an alloplastic material over the defect in the orbital floor) (p= 0.91). Conclusion: There was no significant difference between the transconjunctival approach and the subciliary approach in terms of common postoperative complications such as ectropion and entropion.


Introduction
In recent years, assault, interpersonal violence, motor vehicle accidents (MVA), occupational accidents, and sports injuries have resulted in various physical injuries, including maxillofacial trauma [1]. The oral and maxil-lofacial area is one of the most important anatomical sites in terms of function and esthetics, and about onethird of all injured patients have some type of damage to this area [2]. As this area is one of the most vulnerable parts of the body, fractures in this area can cause serious complications and adverse outcomes for patients. They often cause degrees of deformity and impairment of function, which makes treatment challenging. Therefore, physicians have two types of responsibility toward their patients, which are to repair defects in a way that ultimately results in the relatively same facial appearance as before the trauma and to restore the initial function [3]. The treatment of maxillofacial injuries is very important because of the proximity of this area to vital organs, including the brain and the globe, and because of esthetic issues [4]. The results of fractures in this area differ according to the severity and cause of the trauma, which varies from country to country [5][6]. Today, assault and physical quarrels are among the common causes of maxillofacial fractures [7] and often cause damage to soft tissue, tooth, and bone components [8].
Zygomaticomaxillary complex (ZMC) fracture (ZMC Fx) is the second most common facial fracture after nasal ones due to the prominent position of the zygoma in the facial skeleton. The frequency of these fractures is four times greater in men than in women, and they usually occur in the second and third decades of life. MVA and interpersonal violence are the most common causes of this type of trauma [9]. Bilateral ZMC fractures are rare and comprise about 4% of these fractures. ZMC Fx can disrupt the facial contour, disturb vision, limit ocular movement, and interfere with the function of the mandible [10]. The most common complications in the treatment of ZMC fractures are dehiscence, hematoma, and seroma, lymphedema, a shortening of the lower eyelid, ectropion, entropion, infraorbital nerve disorders, implant infection, diplopia, enophthalmos, blindness, and retrobulbar hemorrhage [9].
Ectropion is an outward curling of the lower eyelid with mild, moderate, and severe degrees. Mild ectropion is when the curling of the eyelid from the globe is low (grade 1), moderate ectropion is when the curling of the eyelid from the globe is associated with the vertical shortening of the lower eyelid (grade 2), and severe ectropion is when true eversion occurs (grade 3). Mild and moderate degrees heal with time and gentle massage, but severe ectropion needs to be treated surgically.
Entropion is the inner curling of the lower eyelid; this condition is less prevalent but more worrisome than ectropion, because it can damage the globe by the eyelashes. Entropion differs in grade from 1 to 4; those with grade 1 have excellent anatomic and functional results, and those with grade 4 have poor outcomes [11]. All grades require corrective surgery. The incidence of ectropion or scleral show with the subciliary approach with skin-muscle dissection has been reported to range from 6% to 18% by different studies [12]. It has also been shown that ectropion is more likely to occur in older people [13]. However, in the study of Appling et al. [14], the incidence of scleral show from treatment using the transconjunctival approach was 3%, and no entropion was observed.
The purpose of the current study was to compare the incidence rates of complications, especially ectropion and entropion, occurring when the transconjunctival or the subciliary approach is used in treating fractures of the ZMC.

Data analysis
The collected data was integrated into the SPSS-21 software and analyzed. Then, mean and standard deviation were used to describe the data and the chi-square test was used to compare the frequencies of ectropion and entropion in the two studied surgical approaches. The significance level in this study was considered as p<0.05.

Results
From 80 patients with fractures, 38 patients underwent surgery with the transconjunctival approach with a mean of 29.63 days between trauma and surgery, and 42 patients underwent surgery with the subciliary approach with a mean of 9.38 days between trauma and surgery.
In both groups, four people had a history of old trauma (more than 1-month interval between trauma and surgery), but all other patients had fresh trauma (less than 1 month); there was no significant differences in surgery times between the two groups. In the transconjunctival approach group, 8% of patients (3/38) were female and 92% (35/38) were male. In the subciliary approach group, the prevalence of males (81%, 34/42) was higher Among patients with entropion, one case was due to MVA and one case was due to motorcycle accident.
In the transconjunctival (84%, 32/38) and subciliary (95%, 40/42) groups, simple trauma had a higher prevalence than comminuted trauma. In patients with ectropion, eight cases had simple trauma and two cases had comminuted trauma; both patients with entropion had simple trauma. There was no significant difference between the two groups regarding the type of trauma (p=0.1).
There were no significant differences between the two groups in terms of the interval between trauma and surgery (p= 0.07), history of massage at the site of surg- Incidence rates of ectropion and entropion in the two studied groups at one month and 5 months after surgery are shown in Table 2 and Table 3, respectively.
The results further indicate that there were no signif-

Discussion
The results of this study indicate that trauma involves men more frequently than women, which is similar to the results of previous studies such as those by Champion et al. [15], Clarke et al. [16], and Boilon et al. [17].
The ratio of men to women in this study was 6 to 1, which is comparable to other studies. In surveys conducted in Canada and Australia, this ratio was reported to be 3 to 1 and 2.5 to 1, respectively. The mean age of patients in this study was 31.98±12.31 years with a minimum of 15 and a maximum of 76 years, which is also similar to the results yielded by previous studies. The higher incidence of maxillofacial fractures in the third decade of life may be due to the fact that people in this period of life are more involved than others in sport activities, high risk occupations, or using high-speed vehicles and are more socially active [18]. In most studies in Iran, such as those by Motamedi [19] and Ansari [20] and the present study, car crashes have been reported as the most common cause of fractures.
In the present study, there was no significant difference in the incidence of ectropion and entropion between  Tenzel and Miller [21] described retroseptal incision. Tessier [22] introduced preseptal incision. Convers et al. [23] added lateral canthotomy to the retroseptal incision, which has a better cosmetic advantage than other common methods, because in this method, the scar is behind the lower eyelid. Other advantages of this method are that it is faster and it does not require skin or muscle dissection [24]. In a similar study by Ridgway et al. [25], the incidence of ectropion in the subciliary treatment group was 14%, and the incidence of entropi- A noteworthy result of the present study was that suspension sutures were used in the transconjunctival approach, and in all but three patients in the subciliary group. Thus, there was no significant difference between the two studied surgical methods in using suspension sutures in preventing ectropion and entropion. This result is similar to that of Bartsich et al. [28]. The patients who received suspension sutures did not have a higher incidence of complications. In the current study, the use of porex produced no significant difference in the incidence rates of ectropion and entropion in orbital reconstruction.

Conclusion
In general, the results of this study showed that there is no significant difference between the transconjunctival method and the subciliary method in terms of postoperative complications such as ectropion and entropion. It should be noted, however, that the limited interval time in this study makes it difficult to interpret the results.
Therefore, in order to achieve results with more accuracy, it is suggested that the present study be repeated